east you're describing is really one where the states that are real and enduring, iran, egypt. >> tunisia. >> turkey to a certain extent. >> absolutely, turkey,y. >> those are the six -- >> because they're age-old clusters of civilization with natural borders. countries like algeria, syria, libya, jordan, were never really thought of until states until the 20 ts century. >> someone once described them as tribes with flags. >> yes. yemen is a mixed bag. even the turks and the british were never able to influence their influence deep into the interior. >> all right. let's look at place where we should know more about the geography, but we don't, which is mexico and the united states. >> yes. >> when you look at this map, what do you see. >> >> whoo i see is the united states is a virtual island. canada's just a thin band of middle class civilization. 33 million people living within a hundred miles of the u.s. border. the united states's real geographic challenge is to the south where much of the border is artificial. where south of the border, you have a country that's so much p